Coven

Vampire Covens are groups of at least three vampires living together. Covens are not very common, as most vampires prefer to travel alone or in pairs, but a few exist stably over long periods of time, even rising to prominence in the vampire world. As most vampires drink human blood, they are wilder and bloodthirstier than "vegetarians" and therefore do not usually get along with each other as well. In large covens, members can easily turn on each other for domination of blood and the coven could be split apart by the feuding members. This is mostly common in North America, where covens are formed to battle other covens for territorial means.

Vampires also don't want to attract attention to themselves and it is harder to stay inconspicuous when there are so many living together.